Traditional techniques for installing electrical fixtures and appliances such as lighting fixtures and fans on walls or ceilings usually require the assistance of a qualified electrician, and the use of a variety of tools and specialized hardware. The procedure for installing or uninstalling such fixtures can also be relatively time consuming, even when formed by experienced installer. In addition to the need for hand-wiring the necessary electrical connections between the fixture and electrical power supply wiring, the installer must make separate mechanical connections for supporting or suspending the fixture in place.
One solution to the problem is disclosed in PCT Application No. PCT/IL99/00499 (“PCT '499”), assigned to the assignee of the present application. PCT '499 discloses a plug and socket combination that permits quick connection of an electrical fixture or appliance at an electrical junction box on a wall or ceiling. The socket is secured on the wall or ceiling near electrical power supply wiring and includes a pair of hollow, female receptacles which receive male electrical prongs carried on the plug. The electrical fixture is secured to the plug. In addition to the quick electrical connection provided by this plug and socket combination, a mechanical connection between the plug and socket carries the mechanical load of the electrical fixture. This solution was less than completely desirable however, because the use the use of two male prongs and corresponding female receptacles prevented the installer from rotating the electrical fixture to a desired orientation.
An improvement to the plug and socket described above is disclosed in PCT Application No. PCT/IL01/01078 (“PCT '078”), also assigned to the assignee of the present application. The plug and socket combination shown in PCT '078 employs arcuately shaped electrical interconnections in the form of ring shaped male plug elements received within correspondingly shaped female receptacle openings. By this arrangement, the plug, along with the electrical fixture to which it is attached, can be freely rotated by the installer to a desire rotational position. However, although the plug and socket shown in PCT '078 can be freely rotated, a problem existed in some applications where it was desirable or necessary to secure the fixture in a fixed position once the fixture was rotated into the desired orientation.
A still further improvement in the art is shown in Israeli Patent Application No. 159032 filed Nov. 24, 2003, assigned to the assignee of the present application. In this Israeli application, a revolvable plug and socket combination is disclosed which includes means for selectively locking the plug and socket against relative rotation. By this feature, a user may lock the fixture against further rotation once the installer has indexed it to a desired orientation.
While each of the quick connect plug and socket combinations described above is quite useful in certain specific applications, further improvements would be desirable in order to provide a universal device that can be used in a wider range of applications and gain widespread acceptance, while satisfying local and national building codes and standards. The present invention is intended to satisfy this need in the art.